The present invention relates to a novel apparatus and method for support of transportable freight containers. More particularly, the present invention relates to a variable height chassis gooseneck that can be adjusted to accommodate differently sized containers.
Freight containers useful for transport by ship, rail, or overland trucking are commonly designed to comply with Marine (I.S.O.) or North American Domestic standards. These standards include provision of a narrow tunnel defined in a front bottom portion of a trailer. The depth of the tunnel must be 120 millimeters (423/32 inches) to allow proper fit of the tunnel over a narrow "gooseneck" portion of an overland trailer chassis. The gooseneck is raised higher than the reminder of the trailer chassis to permit its attachment by a conventional kingpin linkage to a fifth wheel of a truck cab. This arrangement permits reduction of the overall height (as measured from the ground) of the container to legal limits without reduction of inside height of the container.
In recent years, a new type of container commonly known as a "J. B. Hunt" container has become increasingly popular. This type of freight container has a reduced tunnel depth of only 31/8 inches, permitting further increase in the inside height and a slightly narrower tunnel width permitting even further increase in volume of the freight container relative to standard freight containers. However, if one places these containers on a standard height gooseneck, the ground to top of freight container distance is prohibitively increased. In practice, these reduced tunnel depth containers can only be used with a specially designed trailer chassis having a low profile gooseneck. Since ensuring availability trailer chassis of differing configurations is inefficient, costly, and difficult, it would be advantageous to have a trailer chassis adjustable to support either standard or J. B. Hunt reduced tunnel depth freight containers.
The present invention provides a chassis attachable to a fifth wheel of a tractor for hauling a freight container, the chassis having a variable height gooseneck assembly for accommodating either a standard or a reduced tunnel depth freight container seatable on the chassis. The variable height gooseneck assembly includes a first longitudinally extending gooseneck beam and a plate movable to a first position above the longitudinally extending gooseneck beam to support a standard tunnel depth freight container. A plate support element is movably connected to the plate and the longitudinally extending gooseneck beam, with the plate support element being configured to move the plate to a second position that allows supported positioning on the gooseneck assembly of a reduced tunnel depth container.
In one preferred embodiment the plate support element is rotatably connected at a pivot to the longitudinally extending gooseneck beam to permit manual rotation of the plate from its first position to its second position. Conventionally, a gooseneck chassis has two longitudinally extending gooseneck beams positioned to lie in spaced apart, parallel relationship to each other. The plate support element is rotatably connected at a pivot positioned between these first and second longitudinally extending gooseneck beams to permit manual rotation of the plate from its first position to its second position. Additionally, if desired, the plate support element can include a supporting plate of increased width so that both the height and width is increased.
In another preferred embodiment of the present invention, the plate support element is vertically movable rather than rotationally pivoted between first and second positions. Typically, the plate support element includes a pneumatic drive mechanism for raising and lowering the plate. In certain embodiments, the pneumatic drive mechanism includes at least one inflatable tube positioned between the plate and the longitudinally extending gooseneck beam, with the inflatable tube being substantially deflated to bring the plate to its second position to support the reduced tunnel depth container and inflated to bring the plate to its first position to support the standard tunnel depth container.